I build mathematical and computational models of neural processing, with a particular emphasis on representation and learning, and normative analyses of the way that neural circuits realize behaviour. The main focus is on reinforcement learning and unsupervised learning, covering the ways that animals come to choose appropriate actions in the face of rewards and punishments, and the ways and goals of the process by which they come to form neural representations of the world. The models are informed and constrained by neurobiological, psychological and ethological data.